Transfusion data and plasma wastage during study protocols
| Variable | Fixed-ratio group n = 37 | Control group n = 32 | Difference (95% CI)* | p value† |
|---|---|---|---|---|
| Transfusion data | ||||
| Ratio of RBC:FP:PLT achieved,‡ median (IQR) | 1 : 1 : 1 (1 to 1.3 : 1 : 0.8 to 1.3) | 1.7 : 1 : 0.8 (1.2 to 2.3 : 1 : 0.5 to 1.3) | RBC: −0.7 (−1.1 to −0.3) PLT: 0.2 (−0.3 to 0.35) | RBC: < 0.01 PLT: 0.3 |
| Received 1:1:1 ratio, no. (%) | 21 (57) | 2 (6) | 51 (32 to 68) | < 0.01 |
| Received only RBC:FP at 1:1 ratio, no. (%) | 27 (73) | 7 (22) | 51 (31 to 71) | < 0.01 |
| Total no. of RBC:FP:PLT units per patient,§ median (IQR) | 7 : 6 : 8 (6 to 10 : 4 to 8 : 4 to 8) | 7 : 4 : 4 (6 to 14 : 3 to 8 : 0 to 8) | RBC: 0 (−5 to 2.5) FP: 2 (0 to 4) PLT: 4 (−3 to 6) | RBC: 0.6 FP: 0.07 PLT: 0.1 |
| Received FP transfusion, no. (%) | 36 (97) | 26 (81) | 16.0 (1.5 to 30.5) | 0.04 |
| Received PLT transfusion, no. (%) | 34 (92) | 21 (66) | 26.3 (7.6 to 44.9) | 0.01 |
| Received massive transfusion (≥ 10 RBC units in 24 h), no. (%) | 15 (41) | 15 (47) | −6.3 (−29.8 to 17.1) | 0.6 |
| Time to first RBC,¶ min, median (IQR) | 25.5 (14 to 48.5) | 32.5 (13 to 70.5) | −7.0 (−23.5 to 13.5) | 0.8 |
| Time to first FP,¶ min, median (IQR) | 89 (65 to 150) | 113 (81 to 165) | −24 (−60 to 9) | 0.05 |
| Time from first RBC to first FP, min, median (IQR) | 60 (40 to 77) | 78 (49 to 112) | −19 (−45 to −1) | 0.05 |
| Plasma wastage | ||||
| Total FP units thawed, no. | 390 | 289 | NA | NA |
| FP units wasted, no. (%) | 86 (22) | 30 (10) | NA | NA |
Note: CI = confidence interval, FP = frozen plasma, IQR = interquartile range, NA = not applicable, PLT = platelets, RBC = red blood cells, SD = standard deviation.
↵* For continuous data, estimation of the 95% CI for the median difference between the 2 groups was calculated using the bootstrap technique based on 10 000 simulations.
↵† χ2 test or Fisher exact test to compare proportions; Wilcoxon rank-sum test to compare distributions; p values for differences in RBC, FP and PLT utilization between study groups are reported separately.
↵‡ Ratios of RBC:FP and FP:PLT calculated to 1 FP unit. One patient in the fixed-ratio group and 4 in the control group did not receive any FP; p values for the differences in RBC:FP and FP:PLT ratios between study groups are reported separately.
↵§ Absolute number of units of RBC, FP and PLT transfused per patient during study protocols.
↵¶ Time from hospital arrival to transfusion of first unit of RBC or FP; the time was not recorded for 1 patient in the fixed-ratio group.